Could just be a particular trait of that engine.
Dad has one at his place and it needs the choke to go.
I would be very interested in a copy of the manuals and parts lists.
I picked up a GX160 from the scrap yard. Had water in it, i wouldnt call it seized, it was nipped, starter wouldnt budge it but it didnt take much extra effort. Im thinking that i might pull it down and make sure its all good.